Digital cameras comprise a sensor chamber in which is lodged an electronic sensor, such as a charge-coupled device (CCD) sensor or Complementary Metal Oxide Semiconductor (CMOS) sensor, onto which is projected the image of what is seen through the lens of the camera. This sensor can acquire the image projected thereon and convert it into electronic data, which is thereafter forwarded to data processing means provided on the digital camera. The data processing means then converts this electronic data into an image file of known format, such as in JPEG, TIFF or RAW formats, stored thereafter on the memory card of the camera. Of course, this sensor must remain as clean as possible, since impurities deposited thereon can undesirably alter the final image acquired by the camera.
It is inevitable that during normal use of a digital camera, its sensor will become exposed to the atmosphere and its airborne impurities, such as minute airborne dust particles. More particularly, on digital cameras having interchangeable lenses such as digital single-lens reflex (DSLR) cameras, the sensor inevitably becomes exposed to the atmosphere and its impurities whenever the lens is removed from the body of the camera, for example when switching lenses.
To clean the sensor of their digital cameras, digital camera owners have come up with a number of cleaning methods. One cleaning method consists in swabbing the camera sensor with a lint-free cleaning swab wetted with a few drops of dedicated cleaning liquid. Certain prior art cleaning swabs for digital camera sensors comprise a paddle-shaped rigid body defining an elongated handle and a sweeping blade integrally carried at one end of handle. A piece of lint-free cloth is wrapped around and carried by sweeping blade. In one particular embodiment of these prior art cleaning swabs, lint-free cloth is bag-shaped and slipped around sweeping blade, and is tightly held thereon by an elastic band.
To use the swab, the user wets the lint-free cloth with a few drops of cleaning fluid. Thereafter, the cloth-covered sweeping blade is brought into the sensor chamber of is camera, into which the sensor is located, and the user gently scrubs the surface of the sensor therewith. The cleaning liquid wetting cloth dissolves dried specks that may be present on the sensor's surface, such as dried saliva drops blown on the camera's sensor when the camera's owner was switching lenses for example. As the swab is swept across the digital camera sensor, the swab picks up and removes the dust particles and dissolved specks from the sensor surface. The cleaning swab is then withdrawn from the camera's sensor chamber and the cleaning fluid spread on the sensor's surface evaporates.
These paddle-shaped swabs exhibit an annoying disadvantage. These swabs, when used, are generally held in downwardly inclined fashion with their sweeping head pointing downwardly towards the camera's sensor. Thus, when the user wets cloth with cleaning fluid and orients the cleaning swab downwardly so as to direct it towards his camera's sensor chamber, the excess cleaning liquid not absorbed by the fibres of the cloth drips under the influence of gravity against the continuous and impervious surface of the handle's sweeping blade-shaped sweeping blade towards its outer edge. The excess cleaning fluid flowing towards the sweeping blade edge soaks the contact edge of the cloth, and can sometimes seep through and start dripping off the contact edge of cloth. Therefore, excess cleaning fluid can drip onto the camera sensor, or can be pressed out the soaked contact edge when it is swept across the surface of the sensor, resulting in an excessive amount of fluid being smeared onto the surface of the sensor. Moreover, it could be difficult for this excess cleaning liquid to be resorbed into the cloth since the latter's contact edge is already saturated with liquid. The swab is then withdrawn from the sensor chamber. The cleaning fluid can then evaporate, but since an excessive amount of cleaning fluid has been discharged from the cloth and left onto the sensor surface, the evaporation thereof has the tendency to leave streak marks on the surface of the sensor, something that is highly undesirable since such marks can alter the performance of the sensor, in particular the sharpness of the images captured by the sensor.